77/E INFERIOR OOLITE OF THE SHERBORNE DISTRICT. 



By S. S. BUG KM AN, Esq. 



]HE genus Astarte is thus described by Dr. Woodward : 

 " Shell sub-orbicular, compressed, thick, smooth, or 

 concentrically furrowed ; lunule impressed ; ligament 

 external ; epidermis dark ; hinge teeth 2:2, the anterior tooth of 

 the right valve large and thick ; anterior pedal scar distinct ; 

 pallial line simple."* 



There are several recent species but the fossil ones are far 

 more abundant, numbering according to D'Orbigny as many as 

 200 species. 



According to Professor Morris's catalogue, they commenced in 

 the Permian formation, but the greater mass of them is found in 

 the Secondary and Tertiary rocks. . In the secondary rocks we 

 find according to Morris's Catalogue : 



10. Chalk species. 

 18. Upper Oolite species. 

 8. Inferior Oolite species. 

 * Manual of Mollusca, page 299. 



